This invention relates to safety devices for machine tools. More particularly, it comprises a press guard which can be interposed between a worker and a press to prevent the worker from being injured by the press.
With the usual press, the press operator is required to sequentially and continuously place parts into the die or a mold between the platens with his hands. The operator than removes his hands from the die area and usually trips the press operating valve with his hand or foot. This tripping of the press, acting through a valve mechanism, actuates the ram of the press to do work on the mold and/or parts therein. If the operator fails to remove his hand or hands, an accident causing serious personal injury results. If the part or mold is placed incorrectly on the die or press, or an obstruction is otherwise between the platens or dies, and the press is tripped, costly damage to equipment as well as personal injuries to the operator could result.
Safety devices to protect the press operator, and/or guard against damage to the press and dies, are known, but such devices have not been entirely satisfactory. Most prior art press guards are screen-type guards which allow no access to the press area, thereby preventing injuries. In order to obtain any access to the press area, the screen must be removed. Usually, a special switch is provided which turns off the machine when the screen is removed. Unfortunately, there are many circumstances in which it is desirable to obtain at least partial access to the press area without removing the press guard. Consequently, the screen-type guards are a nuisance since they must constantly be removed before access can be obtained. Accordingly, many press operators simply remove the screens and risk injury in order to maintain ready access to the press area.